Editorial: In order to preserve the health of its local economy, Metropolis should not permit a Costmart warehouse department store to open within city limits. It has been demonstrated that when Costmart opens a warehouse department store within a city, the bankruptcy rate of local retailers increases in that city by twenty percent over the next several years.

Which of the following questions would be most useful for evaluating the conclusion of the editorial?
(A) Does the bankruptcy rate of local retailers in a city generally stabilize several years after a Costmart warehouse department store opens?
(8) Do most residents of Metropolis currently do almost all of their shopping at stores within the city limits of Metropolis
(C) Have other cities that have permitted Costmart warehouse department stores within city limits experienced any economic benefits as a result?
(D) Is the bankruptcy rate for local retailers in Metropolis higher than in the average city that has permitted a Costmart warehouse department store within city limits?
(E) Does Costmart plan to hire employees exclusively from within Metropolis for the proposed warehouse department store?
[spoiler]Answer per Manhattan is C.
IMO D. I believe D scores over C as follows:

Denial test: If the rate is lower than those cities, then Costmart will impact. If rate is already higher, then Costmart cannot be held for increase in bankruptcy.

C: If retailers didn't experience any economic benefit, that doesn't mean that Costmart will result in bankruptcy. I feel there is a shift from bankruptcy to lack of economic benefit here.

I acknowledge D doesn't specifically hit the 20% rider, but neither does C. So, D sounds better.[/spoiler]